Square Footage Calculator

Enter length and width in feet, inches, yards, or meters to get the area in square feet, square meters, and acres.

Reviewed by the WorldCalcs team · Methodology · Last reviewed: June 2026

Square feet

120

sq ft

Square meters

11.1483648

sq ft × 0.092903

Acres

0.002754820937

sq ft ÷ 43 560

What is a square footage calculator?

Square footage is the area of a space measured in square feet — the standard for rooms, flooring, lawns, and real estate in the US. Enter the length and width (in feet, inches, yards, or meters) and this calculator returns the area in square feet, square meters, and acres.

How it's calculated

Area is length times width. The calculator first converts both measurements to feet (1 inch = 1/12 ft, 1 yard = 3 ft, 1 meter = 3.28084 ft), multiplies them for square feet, then converts: 1 square foot = 0.09290304 square meters, and 1 acre = 43 560 square feet.

Example

A room 10 feet by 12 feet is 10 × 12 = 120 square feet (about 11.15 square meters). A plot measured in meters, 5 m by 4 m, is 20 square meters, which converts to about 215.28 square feet.

All calculations happen in your browser. Nothing is sent, stored, or tracked.

Results are estimates and may contain errors — for general information only, not professional advice. Always verify before relying on them. Disclaimer

How to use

Enter the length and width, picking the unit for each. The calculator converts everything to feet, multiplies for square feet, and also shows the result in square meters and acres.

Values are rounded to about 6 significant digits.

Frequently asked questions

How do I calculate square footage?+

Multiply length by width, both in feet. A 10 ft by 12 ft room is 120 square feet.

How do I find square footage from inches or meters?+

Convert to feet first, or just pick the unit in the calculator. 1 inch = 1/12 foot; 1 meter = about 3.281 feet.

How many square feet are in an acre?+

One acre is 43 560 square feet.

How do I convert square feet to square meters?+

Multiply by 0.092903. So 100 sq ft is about 9.29 sq m.

How do I find the square footage of a whole house?+

Work out each rectangular room separately, then add the areas together.

What if the room isn't a perfect rectangle?+

Split it into rectangles, calculate each, and add them up; subtract any cut-outs.